Abstract 2243: Clonogenic 3D high throughput screening in mutant KRAS dependent cancer cells - a chemogenomic approach.

Abstract

Activating KRAS mutations are oncogenic and prevalent in multiple tumor types, being found in as high as 90% of pancreatic carcinomas and 50% of colorectal carcinomas. In spite of its attractiveness for therapeutic intervention to date no KRAS-targeted drug therapies have been approved. Most of the reported mutant KRAS directed cellular screening efforts utilize 2-dimensional assays. Because mutant KRAS driven tumor cell lines are much more strongly dependent on activated K-Ras signaling for anchorage independent growth relative to growth when anchored to plastic, we report herein a screening strategy that leverages a 3-dimensional clonogenic growth assay in soft agar. We have performed a multi-cell line parallel phenotypic high throughput screen with our proprietary compound collection to identify pathways, targets and chemical matter with selective anti-tumor activity in mutant KRAS dependent cell lines - a Synthetic Lethal approach. Our strategy has led to the identification of several chemical classes that inhibit the growth of multiple mutant KRAS cell lines of pancreatic and colorectal carcinoma origin, while sparing multiple wild-type KRAS cancer cell lines. Studies to elucidate their molecular mechanisms of action are underway. Citation Format: Malvika Koundinya, Judith Sudhalter, Albane Courjaud, Bruno Lionne, Gaetan Touyer, Luc Bonnet, Isabelle Menguy, Isabelle Schreiber, Christelle Perrault, Stephanie Vougier, Brigitte Benhamou, Daniel Simard, Maria Paola Castaldi, Ronald Tomlinson, Stephan Reiling, Hui Cao, David Harper, Monsif Bouaboula, Jack Pollard, Claudine Grepin, Carlos Garcia-Echeverria, Francisco Adrian, Ivan Cornella-Taracido, Rosalia Arrebola, Aaron J. Morris. Clonogenic 3D high throughput screening in mutant KRAS dependent cancer cells - a chemogenomic approach. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2243. doi:10.1158/1538-7445.AM2013-2243

Complex High-Content Phenotypic Screening

“…Recently, investigators at Abbott Laboratories developed a soft agar colony formation assay that can be adapted to high-content screening, thereby bringing an important secondary assay to the forefront of primary phenotypic screening [47]. This 384-well 3D assay then opened the door for other big pharma screening projects such as the one by Sanofi-Aventis which involved screening 300,000 compounds on five different Kirsten RAt Sarcoma viral oncogene homologue (the most highly mutated and undruggable oncogene in human cancers) (KRAS)-dependent cancer cell lines grown in 3D ECM to identify pathways, targets or chemical matter with selective KRAS antitumor activity [48]. Researchers at Novartis have taken the 384-well colony formation assay even further, mixing normal colon fibroblasts together with colorectal carcinoma cells to achieve therapeutic indices of experimental test compounds [24].…”

Comparative untargeted metabolomic profiling of induced mitochondrial fusion in pancreatic cancer

“…Pancreatic cancer cells often display aberrations of mitochondrial dynamics in favor of mitochondrial fission [1,6], where these organelles take on a fragmented appearance, which appears to be a KRAS-dependent phenomenon [7]. We previously demonstrated that this overactive mitochondrial fission could be therapeutically targeted by disrupting Drp1, increasing expression of Mfn2 genetically, or with the use of leflunomide [1].…”